Any dif between T4 2.0L and 1.8L manifolds?

[Questor]

I have an T4 1.8L EC series engine with FI from a '75 412 that I am slowly rebuilding from 1.8L to 2.0L.

A friend in another city claims he has a set of OEM T4 2.0L manifolds that will work better in my engine instead of the current 1.8L manifolds that I already have. 1 of the manifolds he uses have a pair of holes drilled, but I am not sure these are for FI or what they are for...

Is there any flow design difference between T4 2.0L and 1.8L manifolds? Do Vanagon manifolds fit exactly like earlier T4 square port or oval port manifolds?

Just wondering...

[Piledriver]

The 2.0 BUS manifold runners neck down to ~ 32mm most of the way and step up at either end, do the Vanagon units do that?

All bus manifolds should physically bolt to Bus heads... The runner lengths may vary due to various plenum setups

Post pics of the setup...

Just FYI:
The 2.0 Porsche manifold runners are shorter and the spacing is a tad different at the plenum due to the larger/wider plenum.
They can be carefully tweaked to point the right way, and the gap is bridgeable with hose, maybe even the OEM lengths, but it's VERY close, but a little longer silicone tubing would probably be a good idea.
They won't fit "normal" T4 heads without some careful work with a drill, and you will probably want to match port the heads, as a step down is Bad.

[Questor]

Are these manifolds OK for use with a 2.0L '75 EC series engine with FI? Do 1.8L manifolds have different port sizes than 2.0L manifolds? I realize that heads and the manifolds must be optimized for use. What are the 2 holes drilled underneath one of the manifolds in pic3 for?





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[Piledriver]

Ummm... those are for Weber IDFs or Dellortos. Not stock anything.

Yes those will fit any T4 head, it looks like they are drilled for manifold vacuum, just plug it or use for PCV...

If you have a Vanagon, I think you might have a slight fitment issue, as those stick up over 12" with carbs and std air cleaners attached.

Those go for ~$50+shipping all the time on TOS or Ebay.

[Questor]

Thanks for the reply, PileDriver !

I will steer clear of these for FI use...

Regards, Steve

[Tom Notch]

I believe you posted this topic in the wrong forum for best exposure to knowledgeable peeps.

Would you like it moved to the Fuel Injection or TIV forum?

[jan72]

... just plug it or use for PCV...

Can you really use such holes for PCV? Wouldn't that work like an air leak? Would you have good vacuum at all rpms? Could i just drill one/two intakes like they did in the picture and use it for PCV? Or do i need to drill all four of them and a balance pipe?

[Piledriver]

... just plug it or use for PCV...

Can you really use such holes for PCV? Wouldn't that work like an air leak? Would you have good vacuum at all rpms? Could i just drill one/two intakes like they did in the picture and use it for PCV? Or do i need to drill all four of them and a balance pipe?

Use the google site search for "Ray greenwood pcv" there are some great threads...
I'm going to have to start using the STFs new bookmark feature .

You would best gang all 4 together and put the ~3mm restrictor near where the PCV valve would have been.

CIS works better... No restrictor, 12mm ID line, but needs retuned, pulls a nice low steady vacuum (pressure drop of the meter) that increases with load. AFMs work too, a late Vanagon is set up pretty much the same (but with a restrictor, heated)